Apparatus for making carbon black



May 7, 1946. l. WILLIAMs ET AL 2,399,969

APPARATUS FOR MAKING CARBON BLACK Filed Feb. 15, 1944 2 sheets-sheet 1l RA NHLBMS FRANK W. SELFRWGE VMay 7, 1946. WILLIAMS ET AL 2,399,969 l APPARTUS FORMAKING CARBON BLACK Filed Feb. 15, 1944 2 Sheets-Sheet 2 gmc/rma IRA WILUAMS FRANK W- EnJ-'RIMEIEA @M f I' Mgif/W' Patented May 7, 1946` I APPARATUS non MAKING camion BLACK Ira Williams and Frank W. Sc'ifridge, Borger, Tex.,` assignors to J. M. Huber Corporation, Borger, Tex., a corporation of Delaware' Application AFebruary 15, 1944, Serial No. 522,414

6 Claims. (Cl. 234-2593) This invention relates to new and improved methods and`apparatus for manufacturing carbon black. A

Ordinarily, carbon black is manufactured by burning a gaseous hydrocarbon as it issues from aA number of slotted lava tips which are so positioned below flat metallicsurfaces that the flames impinge and deposit carbon on such surfaces. The carbon as it is formed is scraped olf of the surfaces and collected by means of hoppers. This apparatus is in .a shed having outlets for the gaseous combustion products at the 'top and slotshaped air inlets near the bottom. `The burners and carbon collecting surfaces are positioned in the upper part lof the shed. The air enters through the air inlets in the form of jets of substantial velocity. Such :lets of air cause considerable turbulence in the air rising to the lava tips. The carbon collecting hoppers and at least part of the gas distributing system are positioned near the-bottom of the shed, and the turbulence in the air is considerably increased by the vjets4 ofair striking such accessory apparatus.

In order to obtain thehighest yields of carbon black of the most uniform quality, the ilames from the lava tips should be steady. However, since the gas issuing from the lava` tips 'is at a low velocity, the names are `easily aifected bythe currents of air, and the turbulence in theair, as it rises to the burner tips, causes of carbon black. Also, such turbulence in the air causes currents of, air to impinge uponthe llames so that the air mixes with the flames and causes .they combustionl of an undesirable amount of the" e flames to become unsteady and greatly decr ases the yield The above and other `objects maybe accomyplished in accordance with our invention, which comprises expanding and diffusing the streams .of air entering the shed through the usual air inlets` so that the velocity of the air entering the shed is reduced to less than one-fifth of its original velocity. before it is permltted'to ilow upwardlyto the burners, and the turbulence in the air flowing to the burners is substantially reduced, by placing baillingmearis in the'shed adjacent the air inlets so as to baille and diffuse l the streams of "air,V said means providing air in,

lets of an area at least five times the area of the usual air inlets. By this method Iand apparatus. the turbulence in the air as it reaches the flames is largely eliminated so that the flames are materially more steady and larger yields of carbon black of a more uniform quality are obtained.

Our invention will be more readily understood from the more detailed vdescription which follows when taken in connection withthe accom-` panying drawings,in which: y

Fig. 1 is a somewhat diagrammatical view in vertical `cross-section.showing a conventional carbon blackproducing element, with parts omitted for purposes of clarity in'illustration, and

showing one form of our invention;

Fig. 2 is a side view of the structure of Fig. 1,

v with parts broken away to more clearly show the essential parts of the structure;

Fig. 3'is a detailed cross-sectional view showing a modiiledl form ofthe baiiling means of our inuvention; I

Another object of our invention is to provide improved apparatus which largely eliminates the f turbulence in the air rising to the'ilames, whereby the flames are renderedmore' steady and the yield and quality of the carbon black produced are materially improved.V A further object is to provide apparatus for the usual carbon black shed which will greatly reduce the velocity of the air* advancey theart.8ul1ler obiectswin am!" hereinafter.

. Fig. 4 is a detailed cross-sectional viewshowing another formo! the bailling means of our invention; r

, Fig. `5 isa detailed cross-sectional view showing still another form of the hailing means of ourV invention: l

Fig. 6 isa side view, with parts broken-away,

showing'air guides which may be employed in' y combination with the invention of -thepresent application: and

" Fig. '7 is -a cross-sectional view taken on line r 1-1 or Figc.

, Referring in more detail to Figs. l and 2, the numeral, in represents, a typical burner shed which may be from about 8 to labout 14 feet wide, about 9 to about 14 feet high and vabout 100 to about 200 feet long. This shed is provided with outletsl i2',for the gaseous combustion products. In each side wall i6 of the shed, there is provided a seriesof air inlets il. As is usual., such air inlets may be in the form of slots about one to about three inches wide. about 18 to about 24 inches long and spaced apart by distances equal to or greater than the lengths of the slots. Such slots are usually positioned at from about 6 to about 15 inches above the floor of the shed. The size and number of the slots will, as usual, be determined by therequirements of the shed and the burners to provide the amount of air required to give'the best yields of carbon black of the desired quality.

The amount of air which passes through each slot I4 is further controlled by a. flat sheet .I8 which is larger than and covers the slot on the outside of the shed. 4The air passing through the slot is regulated by the distance of the sheet I8 from the slot, the sheet being bent toward or away from the/wall I8 for this purpose.

Also shown in Figs. 1 and 2, are the usual burner pipes 22 provided with slotted lava tips 24 in the upper portion of the shed I8. Above each burner pipe is provided a` channel iron 20, upon the lower surface of which the carbon is deposited by `the :llames 34 of burning gas impinging upon such surfaces.- A,

The structure, as so far described, is a. common and conventional structure ordinarily used in the manufacture of carbon black. Also included within the burner house will be the usual scraping elements, carbon collecting hoppers and gas distributing system, which are not shown.

' In such apparatus, the air entering through the slots I8 is in the form of jets having a velocity which will usually Avary between about 250 and about 600 feet per minute. This causes turbulence in the air rising to Ithe burner tips24, which turbulence is further increased by the Jets of air impinging upon the collecting hoppers, gas dis.- tributing system and other accessory apparatus in the shed. Such turbulence in the air greatly de-- creases the yield of carbon bycausing the flames to be unsteady and causing the air to impinge upon and mix with the ames.

Also shown inFigs. 1 and 2 is a bailling and diffusing elementv 26 which is one embodiment of our invention. Such diffusing element 28 extends into the shed from the wall Aabove the slots, and, at a substantial distance from the slots, extends downwardly in front of the slots but terminates a substantial distance from the fioorof the shed. A bailling and diffusing element 28 may be provided for each slot, but we have generally found it to be more ldesirable and convenient to provide a single element extending f substantially continuously for the entire length of the shed, forming a single diffuser for all of the slots in a single wall of the shed.

In operation, the Jets of air entering the shed through the .slots i8 strike the downwardly extending wall of the duser element 28, expand in all directions so that the pressure is equalized vand the air then escapes into the shed through the area between the lower edge of the downwardly extending wall of the baille or diffuser and the noor of the burner house. Thus, the space between the lower edge of the downwardly extending wall of the baille 28 and the floor of the burner house forms an air outlet for the air in the space bounded by the baille 28 and thewall il of the burner house. The air passing through auch outlet will have avelocity proportional to the size of the outlet. Generally, such outlet should have an area of. from about to about '10 ormore times as great as the area of the slots Il, whereby the velocity of the streams of air passing through such outlets will be not more than one-ilfth the velocity of the streams aeoaoeo of air passing through the air inlets. By so reducing the velocity of the air entering the main portion of the shed, we are able'to substantially eliminate the turbulence in the air rising to the flames and thus increase the yield of carbon black and produce carbon black of more uniform quality.

In Fig. 3, the hauling and diffusing element consists otia horizontal wall 28 extending into the shed from the wall I6 thereof and positioned above the air inlet i8. At the outer end of the horizontal wall 28, there is provided a vertical wall In extending down in front of the slot Il but terminating a substantial distance from the floor of the shed. 'i In the embodiment shown in Fig. 4, the baille and diffusing element is made of a relatively fine mesh wire screen in the form of a semicircie. We have employed satisfactorily, in such embodiment, ordinary 16 mesh house screen, although screen of different mesh may also be employed, if desired. In this form of baille, we have found that the air will be more uniformly diffused if several layers of screen are employed. With i8 mesh house screen, three or four layers of screen give excellent results. The use of screen in accordance with this embodiment gives the highest reduction in velocity of the air. For example, with slots one inch wide and 8 inches long, a screen diifuser having a radius of 6 inches will increase the area through which the air enters the shed to approximately 71 times the area of the slot. Increasing the radius of the baille will rapidly increase the ratio of the area of the air outlets to the area of the slots.

Fig. 5 represents a modification ofl Fig. 3.

.Where the slot i4 is c1ose to the door ofthe shed,

rection.

Fig. 6 and Fig.' 7 show one embodiment of a form of air guide forming part of the invention disclosed and claimed in our co-pending application Serial No. 368,047 ied November 30, 1940.

This air guide has vertical walls 38 on each side of the burner pipe and extending downwardly a substantial distance below the flames. Near the lower end, the walls are bent slightly inwardly as at 38 and then downwardly at 38 to form a restricted opening 40 to control the velocity of air passing between the guide walls. The guide walls are joined to and separated by partitions 42 hav ing U-shaped openings 44. The partitions 42 rest upon the burner pipe and support the air-guiding structure thereon. 'I'hese air guides operate to further reduce the turbulence in the air and guide the air up to the flame in substantially streamline viscous flow parallel to the direction of the llame. Such air guides are quite etfective' even in the absence of the bai'iiing and diffusing elements, but, in combination with the bailling elements, more completely remove the turbulence from the air and provide conditions more nearly approaching thc`ideal conditions for producing the maximum yield of carbonV black of maximum uniformity in quality.

The sheds and the sheets I8 are ordinarily made installes 3 of sheet iron. They may of course be made of other suitable 4materials having sumcient rigidity for. the purpose and which 'will withstand the temperatures produced in the burner sheds. The' banling andv diffusing elements of our invention I I and the air guides l. may also be made of sheet iron or other sheet metal such as steel, aluminum, nickel, copper, chromium plated metal, nickel plated metal, ceramic or other materials which will have suiilcient strength and rigidity to hold 10 their formand which will withstand the temperatures ordinarily found in apparatus of this type.

The bailling or diusing` members may extend a considerable distance into the shed up to about one-quarter the/width of the shed. It is only 1li l' An experimental burner house, seven lfeet long `by five feet wide by six feet high and containing four collecting channels seven inches wide and six feet long, each of which collected the carbon from 3o fourteen burner tips, was used to prepare carbon black by burning natural gas. y The gas was burned at the ratev of fifty-four cubic feet per tip per twenty-four hours. The tips, having a slot width of 0.044 inch, were spacedat 4.75 inch in- 35 tervals along theburner pipes and were 2.75 inches below the collecting channels. Square pieces of aluminum 'foil were suspended by thin fibers through the area' between the iioor and the burner in the air. The .shed was found to be correctly drafted by two slits one inch wide and eight inches long oneachside of the shed and placed about ten inches above the floor. The slits therefore Prcvidedsrdraftopenings' having a total area of 32 4-5 square inches. The airipassed through the slits at a velocity of 570 feet/minute. Duringoperation of the shed, the aluminum foil indicators 'were in motion in the entire area and were strongly agitated in the lower halfv of the area. .5

The yield of carbon was found to be 2.30 pounds Jper 1,000 vcubic' feet of gas burned.

-A diffusing member was then constructed as shown in Pig. 3. The vertical member was placed six inches in front of the slit, was seven inches 55 high. and the bottom was six inches above the floor.- The diffusing member extended' the length of the burner house. 'I'hus,the diffuser increased f --th'e area of the draft openingsto 1008 square inches or 31.5 umesthat provided by the sut. 0

During operation with the diffusing member in position, the Aaluminum foil indicators were disturbed somewhat near the'fioor, butiwere not dis-4 turbed in the upper portion of the area between thehumer pipes and the door, .The yield of 5 carbon was 2.44 pounds per 1,000 cubic feet of gas burned, an increase of over 6% in yield.

Example 2 Q The experiment of Example 1 was repeated except that the burners were equipped with air guidssample 1 25 1,000 cubic feet of gas burned, an increase of over 4.7% in yield. 4 l

E mmlc 3 A cornmercw unit, consisting of a snee zoo reet in length with ten collecting channels, was ordinarily drafted through 66 two inch slits sixteen inches long spaced about twenty inches apart and ten inches above the floor, the full length ofLeach side of the shed. 'l'he slits therefore provided draft openings having a total area of 4230 square inches, through which the air passed at a velocity of 810 feet/minute. This uni't was equipped with diifusersas shown in Figs. l and2, placed ten inches infront of the draft opening, the lower edge being about six inches from the floor. These diffusera thus increased the area of the draft openings into the shed to 28,800 square inches or 6.6 times that of the slits. The yield of carbon 20 was increased somewhat more than 0.1`pounds per 1,000 cubic feet of gas burned or more than 6%. by the presence of the diffusing members.

It will be understood that the foregoing examples and the modifications shown in the drawings are 'given for illustrative purposes solely, and that various modincations and variations may be made therein without departing from the spirit or scope ofour invention. For example, other forms of the baffling and diffusing elements will occur to those skilled in the art. Further, ywhile we have shown the air inlets I4 in the form of slots in the side walls of the burner shed, it will be apparent that such inlets may take other shapes, may be spaced varying distances above the floor of the burner shed but below the burners. and may be in the end walls or in the door of the burner shed.

We have further introduced the air near the cen-- 'ter of the shed near the bottom thereof by means n of duct workl and, by the use of battling and diffuspipes in order to indicate the degree of'turbulence 4 0 shed and through which streams of air normally enter the shed at a velocity sunicient to cause Substantial turbulence ln the nir adjacent the V burners, gas burners in the upper portion of the shed, carbon collecting members above the burners so placed that the llames. from the burners impinge on the carbon collecting. members and deposit carbon thereon, the improvement which comprises means in the shed adjacent the air in- -lets baiiling and diffusing the streams of air so. that the air enters the shed beyond such 'means a t a velocity of not more than one-fifth the vef loclty at which it passes through the air inlets. 2. In anapparatus for making carbon black by the impingement process which includes al shed having outlets for gaseous products at the' top thereof and small air inlets adjacent the bot- 1 tom thereof controlling the amount of air entering lthe shed and through which. inlets the streams of air normally enter the shed at a veloc-` ity suiiicient to cause substantial turbulence in ingmemberssuchasthoseofrlgaand'l. The

.yieldofcarbomwithoutdiifusersandwithdilusers, was 2.55 and 2.67 pounds, respectively, per l! the air adjacent the burners. gas burners in the upper portion of the shed, carbon collecting members above the burners so placed that flames from the burners impinge on the carbon collecting members and deposit carbon thereon,

assaooo ing upwardly from the bottom of the shed toward the outer edge of the horizontal wall to a point above the air inlet but having its upper edge spaced from the horizontal wall by a distance greater than the width of the air inlet and suilicient to provide an air outlet at least ilve times 3. In an apparatus for makingacarbon "black f by the impingement process which includes a, shed having outlets for gaseous products at the top thereof and small air inlets in the side walls adjacent to .but spaced from the bottom thereof by.

a distance substantially greater than the width vof the inlets controlling the amount of air entering the shed and through winch inlets the streams of air normally enter the shed at a velocity sumcient to cause .substantial turbulence in the airadjacent the burners, gas burners in the upper portion of the shed, carbon collecting members above the burners. so placed that the ilamesfrom the burners impinge on the carbon collecting members and deposit carbon thereon, the improvekment which comprises air-diffusing bailles in the shed adjacent the air inlets, each air-diffusing baille having an upper wall above the air inlet extending substantially horizontally from the wall of the shed into the shed a distance substantially greater than the widthof the air inlet and a substantially vertical wall extending downwardly from the outer edge of the horizontal wall to a point below the air inlet but having its lower edge spaced from the bottom wall of the shed by a distance greater than the width of the air inlet and sufficient to provide an air outlet of an area .40

- at least ve times the areaof the air inlet, so

substantial turbulencein the air adjacent the burners, gas burners in the upper portion of the shed, carbon collecting members above the burners so placed .that the flames from the burners impinge on the carbon collecting members and deposit carbon thereon, the improvement which comprises air-diffusing baiiles inthe shed adjacent the air inlets, each air-diflusing baille having an upper wall spaced above the air inlet by a distance substantially greater than the width of the inlet and extending substantially horizontally from the wall of the shed into the shed a distance substantially greater than the width of the air inlet and a substantially vertical wall extendenter the. shed ata velocity suili lent to cause .the area of the air inlet, so that the streams of air from the air inlets strike the vertical walls, expand and pass through the air outlets at a substantially reduced velocity. v

5. In an apparatus for making carbon black by the impingement process which includes a shed having outlets for gaseous products at the top thereof and small air inlets adjacent thebottom` thereof controlling the amount of air entering the shed and through which the streams of air normally enter the shed at a velocity suilicient ,to cause substantial turbulence in the air adjacent the burners, gas burners in the upper portion of the shed, carbon collecting members above the burners so placed that the flames from the burners impinge on the carbon collecting members and deposit carbon thereon, the improvement which comprises air-diffusing baiiies in the shed adjacent the air inlets extending in front of and above the air inlets and spaced from the air inlets a substantial distance to pr'ovide an expansion chamber for the air, said air-diffusing bailies having walls of Wire screen of approximately 16 mesh to provide air-outlets of an area at least flve times the area of the air inlets, the air-diffusing battles being so positioned that the streams of air from the air inlets strike the bailles. expand andv pass through the air outlets reduced velocity.

6. In an apparatus for making carbon black by the impingement process which includes a shed having outlets for gaseous products at the top thereof and a series of small horizontally spaced horizontal slots in each side wall adjacent the bottom thereof forming air inlets controlling the amount of air entering the 'shed and through which the streams of air normally enter the shed at a velocity sufficient to cause substantial turbulence in the air adjacent the burners, gas burners in the upper portion of the shed, carbon collecting members above the' burners s0 placed that the flames from the burners impinge on the carbon collecting members and deposit carbon thereon, the improvement which comprises air-diffusing bailies in the shed adjacent the air inlets, each air-dlusing baille extending substantially the length of the shed and having walls above the 'air inlets extending from the wall of the shed a substantial distance into the shed and in front of but spaced from the air inlets a substantial distance at a subsiantialbI to form an expansion chamber for the streams of e Velocity. f

IRA WILLIAMS. 7 FRANK W. SELFRIDGE. 

